Hamilton's issue won't kill him either, though a vision problem with a 95 mph fastball traveling toward his head could. He left Tuesday's game in the fourth inning because he didn't want to misjudge a fly ball that could lead to a big inning.

Doctors he saw here Wednesday and Thursday diagnosed a sinus infection and prescribed antibiotics, but the medicine hadn't taken hold before he joined Beltre and his teammates for batting practice.

A sinus infection is nothing new for Hamilton, but the eye issues are a new wrinkle.

"I'm just off. It's just a sick feeling," Hamilton said before the workout. "Sometimes it can cause me to be off-kilter or off-balance. This is the first time it's really caused me to not be able to focus like I need to be able to focus on the field as far as locking in on pitches and fly balls."

Hamilton played with a respiratory infection in May, hitting a walk-off homer to beat Toronto on May 26 on a day he said he was so woozy that he was seeing stars.

He played the next day but sat May 28.

Hamilton said the timing of his illness, as the Rangers try to hold off Oakland for a third straight American League West title, is unfortunate but out of his hands.

"You know what? I'm not going to worry about it," he said. "It's God's timing, not my timing. That's what I live by."

Beltre's doctors have ruled out just about everything that might be causing his discomfort, which started Sunday night. An ulcer and kidney stone have been ruled out, and doctors don't believe the problem is related to the surgery he had to remove his appendix more than 10 years ago.

He is eating, though putting food on his stomach only makes the pain worse.

Beltre underwent tests Wednesday that started at 6 p.m. -- otherwise he would have attempted to play -- and will have another round of gastro-intestinal exams this morning.

"It was frustrating yesterday not being here," he said. "It's more frustrating that I don't know what's going on."

But he took batting practice and fielded grounders at third base before telling manager Ron Washington that he could play. Washington inserted him in the cleanup spot as the designated hitter.

Washington typically prefers to give players another game off after they inform him they are ready to go, but Beltre isn't the typical player and time is running out.

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